8. Changes since RFC 2916(-> 3761^prop)

   Part from clarifications in the text in this document, the major
   changes are two:

   The document uses an explicit DDDS algorithm, and not only NAPTR
   resource records in an "ad-hoc" mode.  In reality this doesn't imply
   any changes in deployed base of applications, as the algorithm used
   for ENUM resolution is exactly the same.

   The format of the service field has changed.  The old format was of
   the form "example+E2U", while the new format is "E2U+example".
   Reason for this change have to with the added subtypes in the
   enumservice, the ability to support more than one enumservice per
   NAPTR RR, and a general agreement in the IETF that the main selector
   between different NAPTR with the same owner (E2U in this case) should
   be first.